Construction, particularly welding and pipe-fitting field work is highly challenging, as most jobs are in large part custom. That is, the assemblies being made must be hand measured, constructed and fitted to a particular job. It is between rare and never that a factory-constructed structure fits properly in the field. Thus, for example pipe-fitting is a complex trade, approaching an art, wherein pipe runs must be measured in the field before welding. Allowances must be made for flanges, elbows, bends and obstructions. The latter is particularly problematic, where an obstruction must be routed-around, and requires complex compound turns or bends to provide the runs of the fewest simple bends. The more bends in a water or steam line, the greater the internal frictional losses, which increases power requirements.
In addition, it is very difficult to align the axes of pipes for welding. The gaps between ends of pipes to be welded should be uniform around the circumference to insure a complete, defect free strong weld. This is particularly difficult in the typical two-stage welding: first tack welding, then full circumferential welding fill-in. When tack welding, the first weld tends to pull one or both pipes out of alignment. The pipe segments must be realigned before the weld cools. In circumferential welding, where the job situation requires welding in arcuate segments of the circumference, as compared to a continuous circumferential weld, defects typically are introduced at the arc junctures.
The need for precision in field jobs goes far beyond welding, extending into cutting, bending, & grinding. Where a precise straight end cut for butt joining or mitering cut is not achieved, the resulting join is necessarily imperfect and subject to failure.
Accordingly, there is a significant unsolved need in the construction trades to have a work station at which precision operations may be accomplished in the field, and which is entirely portable, may be secured, is robust to withstand rough use and bad weather, yet is inexpensive to construct and simple to transport, set up and use.